Rob Gronkowski likes to have a good time, but that does not mean he is stupid. Professional athletes in the National Football League historically have horrible financial problems, according to Fortune, but the New England Patriots tight end recently revealed that he has not touched any of the $16.3 million that he has made from the NFL, according to Business Insider.

In his new autobiography "It's Good to be Gronk," the football player explains that he lives purely off the money he makes from endorsement deals (BodyArmor SuperDrink and Dunkin' Donuts) and appearances.

In an excerpt from the book previewed on TheMMQB.com, Gronk talks about how he lives below his means. He even still wears jeans from high school.

"To this day, I still haven't touched one dime of my signing bonus or NFL contract money," Gronkowski writes. "I live off my marketing money and haven't blown it on any big-money expensive cars, expensive jewelry or tattoos and still wear my favorite pair of jeans from high school... I don't hurt anyone (except Gord with the occasional kick to the groin), I don't do drugs, I don't drive drunk, I don't break the law... I'm a 23-year-old guy just looking to have a fun time."

In a 2012 interview with "Sports Illustrated" Gronk explained that he invested his NFL earnings in tax-free municipal bonds following the advice of his father, Gordy Gronkowski. "It's Good to be Gronk" will hit bookshelves on July 14, according to publisher Simon & Schuster.